The taking of samples, generally referred to by the term biopsy, has become an increasingly frequent medical procedure since it permits, inter alia, operations for diagnosing pathological conditions following various examinations of the sample taken and makes it possible to reach, without causing injury, deep-lying organs such as the liver and kidneys.
Numerous sampling devices have therefore been developed to respond to demand, the aim being to facilitate their use by practitioners and to guarantee very reliable functioning.
Numerous devices for taking samples from the body are already known and these generally comprise:                a needle whose distal end forms a recess able to receive said sample;        a cannula coaxially surrounding said needle, said needle and cannula being able to slide relative to one another;        slides connected respectively to said needle and cannula;        springs connected respectively to said slides;        a grippable housing of elongate shape, defining an inner seat inside which are arranged in series, on a longitudinal axis of said housing, said slides which are able to slide between a forward position in the housing, for which said needle and cannula are in a rest position and ready to be primed for taking a sample, and a rearward position for which said needle and cannula are in a primed, retracted position ready for said sampling;        a control button for bringing said slides to the rearward position counter to said respective springs;        means for blocking said slides in the rearward position; and        a trigger mechanism for canceling said blocking means and, under the action of said springs, causing the forward displacement of said slides and firing of said needle and cannula.        
Such devices are disclosed in, for example, European patents EP-0 238 461 and EP-0 435 986.
These devices described require the practitioner to use both hands to simultaneously charge the slides comprising needle and cannula, counter to the action of springs, which is not always easy to do.